package com.itheima.filter;

import com.itheima.pojo.ums.LoginUms;
import com.itheima.utils.JwtUtil;
import com.itheima.utils.RedisCache;
import io.jsonwebtoken.Claims;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Objects;

@Component
public class JwtAuthenticationTokenFilter extends OncePerRequestFilter {

    @Autowired
    private RedisCache redisCache;

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
        //获取token
        String token = request.getHeader("token");

        //如果没有token。放行，return
        if (!StringUtils.hasText(token)) {
            filterChain.doFilter(request, response);
            return;
        }

        //解析token
        String umsId = null;
        try {
            Claims claims = JwtUtil.parseJWT(token);
            umsId = claims.getSubject();
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException("token非法");
        }
        //从redis中获取用户信息
        LoginUms loginUms = redisCache.getCacheObject("login:" + umsId);
        if (Objects.isNull(loginUms)){
            throw new RuntimeException("用户未登录");
        }

        //存入SecurityContextHolder当中
        //TODO 权限认证
        UsernamePasswordAuthenticationToken authenticationToken=
                new UsernamePasswordAuthenticationToken(loginUms,null,null);
        SecurityContextHolder.getContext().setAuthentication(authenticationToken);

        //放行
        filterChain.doFilter(request,response);
    }
}
